The technology of the present disclosure relates to an image forming device and, more particularly, to an image forming device that includes an intermediate transfer body to which a toner image formed in an image carrier is firstly transferred and a secondary transfer member for secondarily transferring the toner image transferred to the intermediate transfer body to a recording medium.
In general, there is known an image forming device that includes an image carrier such as a photosensitive body or the like, on the surface of which a toner image is formed, an intermediate transfer belt (intermediate transfer body) which rotates in synchronization with the image carrier and to which the toner image formed in the image carrier is firstly transferred, and a secondary transfer roller (secondary transfer member) for secondarily transferring the toner image transferred to the intermediate transfer belt to a transfer paper (recording medium). The image forming device is configured to separate the transfer paper from the intermediate transfer belt and to convey the transfer paper to a fixing unit.
In the image forming device, it is sometimes the case that the secondarily-transferred transfer paper is not separated from the intermediate transfer belt but is stuck to the intermediate transfer belt, consequently generating a paper jam phenomenon. In order to improve this phenomenon, there is extensively used a method in which a separating member from separating a transfer paper from an intermediate transfer belt is installed at the downstream side of a nip portion between the intermediate transfer belt and the secondary transfer roller in a transfer paper conveying direction. In this method, the transfer paper is separated from the intermediate transfer belt by removing electricity from the transfer paper with the separating member.
There is also known an image forming device in which a photo sensor for detecting the kind of a transfer paper is installed and in which the position of a separating member is changed depending on the kind of a transfer paper. In this image forming device, the sticking of a transfer paper to an intermediate transfer belt is restrained by setting an electricity removal amount depending on the kind of a transfer paper.